Method of producing food patties using multiple row molding apparatus

ABSTRACT

A method of operating a multiple row molding apparatus provides greatly increased production of food patty machines. The method comprises the steps of providing a mold plate having front and back cavities in longitudinal and transverse alignment. When the mold plate is at a retracted position, multiple fill slots enable flow of the food product from a manifold simultaneously to all the cavities. At an extended position, all the patties are ejected simultaneously by a knockout mechanism. The fill slots may be either one long fill slot, or multiple short fill slots in communication with respective cavities. In a modified method, food product flows through a single fill slot and communicates only with the front cavities when the mold plate is in its retracted position. As the mold plate advances toward its extended position, the row of back cavities passes over the fill slot and enables the food product to flow into the back cavities.

This is a divisional of U.S. patent application Ser. No. 09/967,153filed Sep. 28, 2001 now U.S. Pat. No. 6,604,935.

BACKGROUND OF THE INVENTION

1. Field of the Invention.

This invention pertains to food processing, and more particularly toapparatus that molds individual patties from a bulk quantity of a foodproduct.

2. Description of the Prior Art.

Various equipment has been developed to make individual food patties ona high production basis. For example, it is well known to load aquantity of ground meat, such as beef or pork, into a hopper of amolding machine. The meat is forced from the hopper through a pump boxand into a manifold. From the manifold, the ground meat flows throughfill slots into multiple cavities in a mold plate. The mold plate withthe filled cavities advances in a longitudinal direction to a knockoutstation, at which the meat is pushed out of the cavities. The mold platethen returns to a fill station for refilling the cavities. U.S. Pat.Nos. 3,486,186; 3,887,964; 3,952,478; 4,054,967; 4,097,961; 4,182,003;4,334,339; 4,343,068; 4,356,595; 4,372,008; 4,535,505; 4,597,135;4,608,731; 4,622,717; 4,697,308; 4,768,941; 4,780,931; 4,821,376;4,996,743; 5,021,025; 5,022,888; 5,655,436; and 5,980,228 arerepresentative of prior machinery for making round patties from bulkquantities of ground meat. U.S. Pat. No. 4,818,446 illustrates a machinefor making generally rectangular patties.

In the machines of all the aforementioned patents, the mold platecavities are arranged in a single row that is transverse to thedirections of mold plate reciprocation. Thus, for each cycle a number ofpatties is produced that is equal to the number of cavities in the moldplate.

To increase the production rate of producing the patties, it wasnecessary that the prior mold plates reciprocate faster. However, therewas a practical limit as to how fast the prior machines could operate.The limitations were based on the acceleration forces produced on thereciprocating components, and also on the ability of the meat product toflow from the manifold through the fill slots into the mold platecavities. For most prior machines, the practical limit was approximately90 cycles per minute. If that production rate was insufficient, it wasnecessary for the processing plant to acquire more machines.

U.S. Pat. No. 4,975,039 describes a food molding machine having a moldplate with two transverse rows of cavities. A knockout station isbetween two fill stations. While one row of the mold plate cavities isbeing filled at a first fill station, the second row is at the knockoutstation. The mold plate reciprocates to bring the first row to theknockout station and the second row to the second fill station. Themachine of the U.S. Pat. No. 4,975,039 patent is able to produce twiceas many patties per cycle as machines with only one row of cavities.However, an attendant disadvantage is the cost and complexity of amachine having two separated fill stations.

U.S. Pat. No. 4,872,241 teaches a patty molding machine having a moldplate with two transverse rows of cavities. The cavities are elongatedfor handling a whole muscle meat product rather than a ground meatproduct. The cavities are staggered in the longitudinal direction tomake the two rows. No cavity in either row is aligned longitudinallywith any other cavity. Each cavity has its own individual fill slot. Allthe cavities are filled simultaneously at the fill station.

U.S. Pat. No. 4,338,702 depicts a mold plate with two rows of cavities.The cavities in one of the rows are used only as passages between themanifold and plug-forming cavities on the opposite side of the moldplate as the manifold. Only the cavities in the other row receive meatproduct for making patties, and only the patties in that row of cavitiesare knocked out at the knockout station.

In spite of the numerous designs of patty producing machines available,there is room for further developments to them.

SUMMARY OF THE INVENTION

In accordance with the present invention, a double row molding apparatusis provided that greatly increases the productivity of food pattymachines. This is accomplished by apparatus that includes a mold platehaving pairs of longitudinally aligned cavities and a knockout mechanismthat ejects food product from all the cavities simultaneously.

Each pair of mold plate cavities has a front cavity and a back cavity.The front cavities of the pairs are aligned in a front transverse row,and the back cavities of the pairs are aligned in a back transverse row.

The mold plate has a top surface that is in flat facing contact with abreather plate. A bottom surface of the mold plate is in flat facingcontact with a top plate and with a filler plate that is installed intothe top plate. A drive mechanism reciprocates the mold plate inlongitudinal directions between a retracted position and an extendedposition. At the retracted position, the mold plate cavities are betweenthe breather plate and the filler plate. Food product is forced from amanifold through fill slots in the filler plate into the mold platecavities. At the extended position, the cavities overhang the breatherplate and the top plate, and the cavities are open at both top andbottom surfaces of the mold plate. The knockout mechanism ejects foodpatties from all the cavities simultaneously. The mold plate thenretracts back to the retracted position for refilling the cavities, andthe cycle continues. Thus, for each cycle, twice as many patties areproduced as was possible using the prior machines that had a single rowof cavities.

According to one aspect of the invention, there is a single long fillslot in the filler plate. The row of front cavities is in communicationwith the fill slot, but the back cavities are not in communication withthe fill slot when the mold plate is at its retracted position. Rather,the row of back cavities are sealed from the fill slot by the close fitof the mold plate top and bottom surfaces with the breather plate andthe top plate, respectively. Preferably, the fill slot is closer to thetrailing edges of the mold plate front cavities than to the leadingedges of the cavities. Food product is forced from the manifold throughthe fill slot only to the front cavities when the mold plate is at itsretracted position.

The mold plate then advances toward its extended position. After only ashort advancement, the front mold plate cavities lose communication withthe fill slot. On the other hand, the advancing mold plate causes theback cavities to pass over the fill slot. As the back cavities pass overthe fill slot, the food product, under pressure, flows through the fillslot into the back cavities. The flow of the food product into the backcavities completely fills them, which may have been partially filledpreviously, as will be explained shortly. When the mold plate is at itsextended position, the back cavities have completely passed the fillslot, and the fill slot is sealed off from all the cavities. Theknockout mechanism operates to eject the food product simultaneouslyfrom all the cavities.

During the mold plate return stroke, the back cavities again pass overthe fill slot. Any residual pressure on the food product in the manifoldwill cause the food product to flow through the fill slot into the backcavities and partially fill them. At the end of the return stroke, whenthe mold plate is again at its retracted position, the front cavitiesare again over the fill slot, and the back cavities are sealed off fromthe fill slot. The mold plate dwells momentarily at the retractedposition, during which time the front cavities are filled. The moldplate then advances forward. As they pass over the fill slot, the backcavities are completely filled, and the cycle repeats. It is thus seenthat the back cavities fill with the food product during both forwardand return strokes, but not during the mold plate dwell at the end ofthe return stroke. On the other hand, the front cavities fill onlyduring the dwell at the end of the return stroke and not during eitherthe forward or return strokes. Rather than one long fill slot thatcommunicates with all the mold plate cavities, the filler plate may havemultiple short fill slots each associated with a respective pair offront and back cavities.

In another embodiment of the invention, there are single long front andback fill slots. The front fill slot communicates with the row of frontmold plate cavities when the mold plate is at its retracted position,and the back fill port communicates with the row of back cavities. Thefront fill slot may be close to the trailing edges of the mold platefront cavities, and the back fill slot may be close to the leading edgesof the back cavities. During the dwell of the mold plate at theretracted position, food product flows from the manifold through the twofill slots into all the cavities simultaneously. During the forwardstroke of the mold plate, the front cavities quickly lose communicationwith the front fill slot. On the other hand, the back cavities of themold plate pass over and temporarily communicate with the front fillslot. Any residual pressure of the food product tends to force itthrough the front fill slot into the back mold plate cavities.Consequently, the back mold plate cavities are fillable from both theback and front fill slots. When the mold plate has advanced to itsextended position, the knockout mechanism ejects the food patties fromall the cavities simultaneously.

During the mold plate return stroke, the back cavities pass over thefront fill slot. Any residual pressure on the food product causes it toflow through the front fill slot into the back cavities. The backcavities can thus be partially filled during the mold plate returnstroke. When the mold plate has returned to its retracted position, itdwells there momentarily while the food product flows through the frontand back fill slots into the front and back cavities, respectively.Because the front cavities fill only during the dwell time, whereas theback cavities fill both during the dwell time and during the forward andreturn strokes of the mold plate, the front fill slot preferably has alarger cross-sectional area than the back fill slot.

If desired, the front fill slot that communicates with all the frontcavities can be several short fill slots each in communication with arespective front cavity when the mold plate is at its retractedposition. Similarly, several short back fill slots can be used insteadof one long back fill slot.

To eject the food patties from the mold plate, the knockout mechanism ofthe invention has two rows of knockout cups on a single knockout bar.The knockout bar is attached to a pair of knockout slides that areguided for vertical reciprocation in respective guides. Each of a pairof knockout arms has a first end that engages a respective knockoutslide. Each knockout arm is pivotally connected between its ends to ahousing that is part of the double row molding apparatus. Inside thehousing is a shaft with a pair of cams. The cams are in contact withsecond ends of the knockout arms. The shaft and cams rotate in timedrelation to the reciprocation of the mold plate. For all positions ofthe mold plate except its extended position, the cams hold the knockoutcups against a spring force away from the mold plate. When the moldplate is at its extended position, the cams allow the spring force toreciprocate the knockout cups to if eject all the patties from the moldplate simultaneously.

The method and apparatus of the invention, using double rows oflongitudinally aligned cavities in a mold plate, thus improvesproductivity of a meat patty machine. The probability of producingimperfect patties is remote, even though the back cavities are fillableon both forward and return strokes of the mold plate.

Other advantages, benefits, and features of the present invention willbecome apparent to those skilled in the art upon reading the detaileddescription of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a broken partial front view of a food patty machine thatincludes the double row molding apparatus of the invention and showingthe mold plate at its extended position.

FIG. 2 is a longitudinal cross-sectional view on an enlarged scale of aportion of the double row molding apparatus of the invention showing themold plate in its retracted position.

FIG. 3 is a view taken along line 3—3 of FIG. 2.

FIG. 4 is a view similar to FIG. 3, but showing the mold plate at itsextended position.

FIG. 5 is a simplified longitudinal cross-sectional view of a modifiedembodiment of the invention showing the mold plate at its retractedposition.

FIG. 6 is a view similar to FIG. 5, but showing the mold plate at itsextended position.

FIG. 7 is a view taken along line 7—7 of FIG. 5.

FIG. 8 is a view taken along line 8—8 of FIG. 6.

FIG. 9 is a view generally similar to FIG. 3, but showing single longfront and back fill slots.

FIG. 10 is a view generally similar to FIG. 7, but showing a single longfill slot.

FIG. 11 is a simplified top view of the knockout mechanism of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

Although the disclosure hereof is detailed and exact to enable thoseskilled in the art to practice the invention, the physical embodimentsherein disclosed merely exemplify the invention, which may be embodiedin other specific structure. The scope of the invention is defined inthe claims appended hereto.

General

Referring first to FIGS. 1 and 2, a portion of a food patty moldingmachine 1 is illustrated that includes the present invention. A typicalprior food patty molding machine is manufactured by Formax, Inc. ofMokena, Ill. However, the particular food patty machine 1 is notcritical to the invention.

Briefly by way of background, the food patty molding machine 1 includesa large hopper, not illustrated in the drawings, that contains aquantity of a food product such as ground meat. The food product ispushed by well known means through a pump box (not shown) toward amanifold 3. A rotary valve 5 at the entrance of the manifold 3 eitherenables or prevents the food product from entering the manifold. Fromthe manifold, the food product is forced through a filler plate 7 into amold plate 9 that has a bottom surface 12 and a top surface 24. Thefiller plate 7 is installed in a top plate 8. The mold plate 9 isassembled between the filler plate 7 and top plate 8, and a breatherplate 10. The mold plate reciprocates in longitudinal directions, asshown by arrows 11 and 13, between extended and retracted positions. Aknockout mechanism 15 ejects patties 16 of the food product from themold plate when the mold plate is at its extended position, as is shownat reference numeral 9A in FIG. 1.

First Embodiment

In accordance with the present invention, and also looking at FIGS. 3and 4, the mold plate 9 is constructed with rows of front and backcavities 17A and 17B, respectively, that receive the food product fromthe filler plate 7. The front cavities 17A are aligned along a fronttransverse centerline 14. The back cavities 17B are aligned along a backtransverse centerline 20. The rows of cavities are arranged into pairsof one front cavity and one back cavity. The cavities of each pair arealigned along respective longitudinal centerlines 18.

The cavities 17A and 17B are shown as being circular in shape. However,oval and other shapes are also within the scope of the presentinvention. Each cavity 17A has a leading edge 17AL and a trailing edge17AT. Similarly, each back cavity 17B has a leading edge 17BL and atrailing edge 17BT. The row of front cavities is next to a front section19 of the mold plate 9. The mold plate front section 19 terminates in afront edge 21. The mold plate has openings, which may be in the form ofslots 50, next to the front edge 21. The slots 50 receive pins frombelow the mold plate that are part of a linkage mechanism thatreciprocates the mold plate in the longitudinal directions 11 and 13.There are shallow grooves 22 in the mold plate top surface 24 betweenthe back cavities and the back edge of the mold plate. The grooves 22fill with fluid during operation of the patty molding machine and aid inlubricating the mold plate.

In the particular construction shown in FIGS. 2-4, the filler plate 7has a front row of fill slots 23A and a back row of fill slots 23Bthrough it. Both rows of fill slots 23A and 23B open into the manifold3. Preferably, the fill slots 23A of the front row are transverselyaligned with each other, and the fill slots 23B of the back row aretransversely aligned with each other. The fill slots illustrated haverespective lengths in the transverse direction that are generally equalto the diameters of the mold plate cavities 17A and 17B. However, thefill slots may have other lengths, if desired. The fill slots 23A of thefront row have a larger cross-sectional area than the fill slots 23B ofthe back row.

In FIGS. 2 and 3, the mold plate 9 is shown at its retracted position.In that situation, the cavities 17A of the front row are over associatedfill slots 23A and the mold plate back cavities 17B are over the backfill slots 23B. According to one aspect of the invention, the fill slots23A are closer to the trailing edges 17AT of the front cavities 17A thanto their leading edges 17AL when the mold plate is at its retractedposition, and the back fill slots 23B are closer to the leading edges17BL of the back fill slots 17B than to their trailing edges 17BT. Asmentioned, the lengths of the fill slots in the transverse direction inthe particular construction shown are approximately equal to thediameter of the mold plate cavities. Consequently, there is an overlapportion 26 and a communicating portion 28 of each front fill slot 23Awhen the mold plate is at its retracted position. Similarly, there is anoverlap portion 30 and a communicating portion 32 of each back fill slot23B.

While the mold plate 9 is at its retracted position, the food product inthe manifold 3 is forced through the fill slots 23A and 23B into themold plate cavities 17A and 17B, respectively. When the cavities arefilled with the product, the mold plate advances in the direction ofarrow 11 toward its extended position, as shown at reference numeral 9Ain FIGS. 1 and 4. It will be noticed that after a short advancement ofthe mold plate, the front cavities 17A lose communication with the fillslots 23A. Consequently, it is vital that the fill slots 23A havesufficient cross-sectional area to completely fill the cavities 17Abefore the mold plate forward stroke begins.

On the other hand, advancement of the mold plate 9 in the forward stroke11 does not result in immediate loss of communication of the backcavities 17B with the associated fill slots 23B. Rather, the backcavities 17B remain in communication with the respective fill slots 23Buntil the trailing edges l7BT of the cavities have passed the back fillslots. Consequently, a smaller cross-sectional area for the back fillslots 23B is sufficient to enable the back cavities to completely fill.Moreover, the back cavities pass over the front fill slots 23A duringthe forward stroke of the mold plate. Any residual pressure of the foodproduct in the manifold 3 causes the food product to flow through thefront fill slots into the back cavities and thus further assures thatthe back cavities are completely filled before they pass completely pastthe front fill slots.

When the mold plate is at its extended position 9A, the section 25 ofthe mold plate overhangs the top plate 8 and the breather plate 10. Theknockout mechanism 15 ejects the food patties 16 from the two rows ofcavities 17A and 17B simultaneously when the mold plate is at itsextended position. For that purpose, the knockout mechanism comprises afront row of knockout cups 27A and a back row of knockout cups 27B. Theknockout cups 27A and 27B align with the mold plate cavities 17A and17B, respectively, when the mold plate is at its extended position. Thepatties fall by gravity onto a conveyor or similar transfer device,schematically represented by reference numeral 29, that conveys them ina downstream direction 11A for further processing.

As soon as the knockout mechanism 15 has ejected the patties 16 from themold plate 9, the mold plate begins its return stroke, arrow 13. As theback mold plate cavities 17B pass over the front fill slots 23A, anyresidual pressure on the food product in the manifold 3 causes a smallamount of the product to flow through the front fill slots into therespective back cavities. Similarly, any residual product pressure alsocauses the product to flow through the back fill slots 23B into therespective back mold plate cavities 17B. No product flows from the frontfill slots 23A into the front cavities 17A until the mold plate isalmost fully at its retracted position. During a short dwell of the moldplate at its retracted position, the rotary valve 5 in the manifoldoperates to enable full force to be applied to the food product. A fullcharge flows through the front fill slots into the front mold platecavities 17A. Simultaneously, food product flows through the back fillslots into the back mold plate cavities. When the front mold platecavities are filled, the mold plate again advances in the forwardstroke, arrow 11, and the cycle is complete. It is thus seen that foreach cycle, twice as many patties 16 are produced by means of thepresent invention than were produced by prior equipment that also hadbut a single fill station.

Turning to FIG. 9, a filler plate 45 may be used that has a single longfront fill slot 36A and a single long back fill slot 36B. The singlelong fill slots 36A and 36B function essentially the same as themultiple short fill slots 23A and 23B, respectively, of the filler plate7 described previously in conjunction with FIGS. 2-4. The single frontfill slot 36A has a larger cross-sectional area than the single backfill slot 36B.

Second Embodiment

Further in accordance with the present invention, two rows of cavitiesin a mold plate are supplied by a single row of transversely alignedfill slots. FIGS. 5-8 show a food patty machine 31 having a manifold 3′with a rotary valve 5′. A filler plate 33 is installed in a top plate8′. The filler plate 33 has a single row of multiple fill slots 34. Abreather plate 10′ is on the opposite surface of a mold plate 35 as thefiller plate and the top plate 8′. The mold plate 35 reciprocates inforward strokes 11′ and return strokes 13′.

In the mold plate 35 are a row of front cavities 37A and a row of backcavities 37B. The cavities 37A and 37B are shown as ovular in shape, butround or other shapes are also acceptable. Each cavity 37A has a leadingedge 37AL and a trailing edge 37AT. Each back cavity 37B has a leadingedge 37BL and a trailing edge 37BT. The cavities are arranged inlongitudinally aligned pairs. Each pair of cavities is longitudinallyaligned with a respective fill slot 34.

FIGS. 5 and 7 show the mold plate 35 in its retracted position. In thatsituation, the row of back cavities 37B are completely sealed off fromthe manifold 3′. The row of front cavities 37A are in communication withthe respective fill slots 34. In the preferred embodiment, the backsurfaces 38 of the fill slots are vertically aligned with the trailingedges 37AT of the respective cavities 37A when the mold plate is at itsretracted position. Accordingly, there is a portion 40 on the ends ofeach fill slot that is overlapped by the mold plate, thus leaving acenter portion 42 in communication with the respective cavities.

When the mold plate is at its retracted position, the rotary valve 5′opens to cause food product in the manifold 3′ to flow through the fillslots 34 into the respective front cavities 37A. After a dwell timesufficient to fill the front cavities 37A, the mold plate 35 advances inits forward stroke, arrow 11′, toward its extended position 35A, FIGS. 6and 8. As the back cavities 37B pass over the respective fill slots 34,food product is forced into the back cavities. The food product is ableto flow into the back cavities for the full time those cavities are overthe respective fill slots. As a result, the back cavities are completelyfilled by the time they have passed the fill slots. At the extendedposition 35A of the mold plate, section 39 thereof overhangs the topplate 8′ and the breather plate 10′.

A knockout mechanism 15′ has front and back rows of knockout cups 41Aand 41B, respectively, that align with the front and back cavities 37Aand 37B, respectively, when the mold plate is at its extended position35A. The knockout mechanism 15′ reciprocates the knockout cups 41A and41B in the directions of arrows 43 to eject patties from all the moldplate cavities simultaneously.

The mold plate 35 then retracts in its return stroke, arrow 13′. Anyresidual pressure on the food product in the manifold 3′ and fill slots34 will cause the product to flow into the mold plate back cavities 37Bduring the return stroke. When the mold plate is fully at its retractedposition, FIGS. 5 and 7, it dwells there long enough to completely fillthe front cavities 37A, and the cycle is complete.

In an alternate embodiment, a single long fill slot can be used insteadof a row of multiple fill slots. In FIG. 10, a filler plate 47 has asingle long fill slot 49. The fill slot 49 communicates with all the rowof front cavities 37A′ when the mold plate 35′ is at its retractedposition. The single long fill slot 49 functions in the same fashion asthe row of multiple short fill slots 34 described above in connectionwith FIGS. 5-8.

Knockout Mechanism

The knockout mechanisms 15 and 15′ constitute an important part of thepresent invention. The knockout mechanism 15′ will be described inconjunction with the food patty machine 31 and mold plate 35. However,it will be appreciated that the knockout mechanism 15 used with themachine 1 and mold plate 9 is substantially similar to the knockoutmechanism 15′.

The knockout mechanism 15′ comprises a knockout bar 44 that holds allthe knockout cups 41A and 41B. As best seen in FIG. 11, the knockout bar44 has a main transverse strip 46 and a number of longitudinalprojections 48. A pair of front and back knockout cups is held to eachlongitudinal projection 48, as by conventional fasteners 51.

The knockout bar 44 is reciprocated in the directions of arrows 43 by apair of knockout slides 53. The knockout slides 53 are guided inrespective guides 55 that are attached to a mold cover 56 that is partof the machine 31. To reciprocate the knockout slides and knockout bar,the knockout mechanism 15′ further comprises a knockout arm 57 and a cam58 in operative association with each knockout slide. Each knockout arm57 has a first end 59 that engages the associated knockout slide, as,for example, by fitting into a slot in the knockout slide and beingpinned to the knockout slide. The knockout arm second end 61 contactsthe associated cam 58. Between the ends 59 and 61 of each knockout armis a pivot 63 with the housing 56. A spring 66 between the pivot 63 andfirst end biases the knockout arm in a clockwise direction with respectto FIG. 5. The cam 58 has a single lobe 67.

The cams 58 are connected to a common shaft 68. The shaft 68 rotates ata constant speed in the direction of arrow 65 8 in timed relation withthe reciprocation of the mold plate 35. The timing is such that theknockout-cups 41A and 41B are away from the mold plate for all parts ofthe mold plate cycle except when the mold plate is at its extendedposition. When the mold plate is at its extended position, the camorientation is such that the knockout arms second ends 61 enter thedepressions 69 on the ends of the cam lobes 67. The springs 66 force theknockout arms clockwise with respect to FIG. 5 such that the knockoutcups contact the patties in the mold plate cavities 37A and 37B andeject the patties from the mold plate. Continued rotation of the shaftcauses the cam lobes to pivot the knockout arms in the reverse directionand reciprocate the knockout cups away from the mold plate, and thecycle repeats.

Summary

In summary, the results and advantages of food patty machines can now bemore fully realized. The double row molding apparatus of the inventionprovides greatly increased production of food patties from a generallyconvention molding machine. This desirable result comes from using thecombined functions of the double rows of cavities in the mold plate andthe two rows of multiple fill slots 23A and 23B in the filler plate 7.The front and back cavities are filled simultaneously during a shortdwell of the mold plate at its retracted position. In addition, foodproduct is able to flow into the back cavities from the front fill slotsas the mold plate advances toward its extended position. Food pattiesare ejected from all the cavities simultaneously when the mold plate isat its extended position. If desired, single long fill slots 36A and 36Bcan be used in place of the multiple fill slots 23A and 23B,respectively. In a modified embodiment, a single row of multiple fillslots 34 supplies both the front and back mold plate cavities. The frontcavities are filled during the dwell of the mold plate at its retractedposition. The back cavities are filled as they pass over the fill slots34 during the mold plate advance stroke. The back cavities may bepartially filled as they pass over the fill slots 34 during the moldplate return stroke. A long single fill slot 49 may be used instead ofthe multiple fill slots 34.

It will also be recognized that in addition to the superior performanceof the double row molding apparatus of the invention, its constructionis such to be of modest cost when compared to the benefits it provides.In fact, an investment in the present invention quickly pays for itselfbecause of the greatly increased production available from a food pattymolding machine.

Thus, it is apparent that there has been provided, in accordance withthe invention, a double row molding apparatus that satisfies the aimsand advantages set forth above. While the invention has been describedin conjunction with specific embodiments thereof, it is evident thatmany alternatives, modifications, and variations will be apparent tothose skilled in the art in light of the foregoing description.Accordingly, it is intended to embrace all such alternatives,modifications, and variations as fall within the spirit and broad scopeof the appended claims.

We claim:
 1. A method of making food patties comprising the steps of: a.reciprocating a mold plate in a return stroke to a retracted position;b. flowing a first quantity of a food product from a manifold into onlya row of front cavities in the mold plate when the mold plate is at theretracted position thereof; c. advancing the mold plate in a forwardstroke to an extended position; d. flowing a second quantity of the foodproduct from the manifold into a row of back cavities in the mold plateduring the forward stroke; and e. simultaneously ejecting the foodproduct from all the cavities simultaneously when the mold plate is atthe extended position thereof.
 2. The method of claim 1 wherein: a. thestep of flowing a first quantity of a food product comprises the step offlowing a first quantity of the food product through a single fill slotthat communicates only with all the front cavities when the mold plateis at the retracted position thereof; and b. the step of flowing asecond quantity of a food product comprises the step of flowing a secondquantity of the food product through the fill slot to all the backcavities during the mold plate forward stroke.
 3. The method of claim 1wherein the step of flowing a first quantity of a food product comprisesthe steps of: a. flowing a first quantity of the food production in afirst direction out of the manifold; and b. flowing the food product inthe first direction into the row of front mold plate cavities.
 4. Themethod of claim 1 wherein the step of flowing a first quantity of a foodproduct comprises the step of flowing a first quantity of a food productthrough multiple fill slots simultaneously to all the front mold platecavities and simultaneously blocking any flow of the food product to therow of back mold plate cavities when the mold plate is at the retractedposition thereof.
 5. The method of claim 1 comprising the further stepsof: a. reciprocating the mold plate in a return stroke from the extendedposition toward the retracted position thereof; and b. flowing a thirdquantity of the food product from the manifold sequentially firstly intoonly the row of back cavities and secondly into only the row of frontcavities during the mold plate return stroke.
 6. The method of claim 4comprising the further steps of: a. reciprocating the mold plate in areturn stroke from the extended position toward the retracted positionthereof; and b. flowing a third quantity of the food product from themanifold through multiple fill slots sequentially firstly into only therow of back cavities and secondly into only the row of front cavitiesduring the mold plate return stroke.
 7. The method of claim 2 comprisingthe further steps of: a. reciprocating the mold plate in a return strokefrom the extended position thereof to the retracted position thereof;and b. flowing a third quantity of the food product through the fillslot into the back cavities and simultaneously blocking any flow of thethird quantity of the food product through the fill slot into the frontcavities during the mold plate return stroke.
 8. A method of producingfood patties comprising the steps of: a. providing a mold plate thatdefines a plurality of rows of transversely spaced and longitudinallyaligned cavities each having a trailing edge and a leading edge; b.providing a fill plate having a number of rows of transversely alignedfill slots equal to the number of the rows of mold plate cavities; c.reciprocating the mold plate in a return stroke to a fill position; d.aligning the rows of mold plate cavities with the respective rows offill plate fill slots; e. flowing a food product out of a manifold in afirst direction; f. flowing the food product in the first directionsimultaneously through the fill slots; g. flowing the food product inthe first direction simultaneously into the respective rows of moldplate cavities; h. advancing the mold plate in a forward stroke to anextended position; and i. simultaneously ejecting food product pattiesfrom all the mold plate cavities.
 9. The method of claim 8 wherein: a.the step of providing a mold plate comprises the step of providing themold plate with a row of front cavities and with a row of back cavities;b. the step of providing a fill plate comprises the step of providing afill plate with a single front fill slot and with a single back fillslot; and c. the step of flowing a food product comprises the steps of:i. flowing the food product through the front fill slot into the row ofmold plate front cavities at locations closer to the respective trailingedges than to the leading edges thereof; and ii. flowing the foodproduct through the back-fill slot into the row of mold plate backcavities at locations closer to the respective leading edges than to thetrailing edges thereof.
 10. The method of claim 8 wherein: a. the stepof providing a mold plate comprises the step of providing the mold platewith a row of front cavities and with a row of back cavities; and b. thestep of providing a fill plate comprises the step of providing a fillplate with a front fill slot having a first cross-sectional area, andwith a back fill slot having a second cross-sectional area less than thefirst cross-sectional area.
 11. A method of producing food pattiescomprising the steps of: a. providing a mold plate that defines multiplerows of transversely and longitudinally aligned cavities including a rowof front cavities and a row of back cavities, each cavity have a leadingedge and a trailing edge; b. reciprocating the mold plate to a retractedposition; c. flowing food product into the row of mold plate frontcavities at locations closer to the respective trailing edges than tothe respective leading edges thereof, and simultaneously flowing foodproduct into the row of mold plate back cavities at locations closer tothe respective leading edges than to the tespective trailing edgesthereof; d. reciprocating the mold plate to an extended position; and e.simultaneously ejecting food product patties from all the mold platecavities.
 12. The method of claim 11 wherein the step of flowing foodproduct comprises the steps of: a. flowing food product in a firstdirection out of a manifold; and b. flowing food product in the firstdirection through multiple front fill slots into the row of mold platefront cavities, and simultaneously flowing food product in the firstdirection through multiple back fill slots into the row of mold plateback cavities.
 13. The method of claim 11 wherein the step of flowingfood product comprises the steps of: a. flowing food product in a firstdirection out of a manifold; and b. flowing food product in the firstdirection through a single front fill slot into the row of mold platefront cavities, and simultaneously flowing food product in the firstdirection through a single back fill slot into the row of mold plateback cavities.
 14. The method of claim 11 wherein the step of flowingfood product comprises the steps of flowing the food product into therow of mold plate front cavities through respective front fill slotseach having a first cross-sectional area, and simultaneously flowing thefood product into the row of mold plate back cavities through respectiveback fill slots each having a cross-sectional area less than the firstcross-sectional area.
 15. The method of claim 11 wherein the step offlowing food product comprises the steps of flowing the food productinto the row of mold plate front cavities through a single front fillslot having a first cross-sectional area, and simultaneously flowing thefood product into the row of mold plate back cavities through a singleback fill slot having a cross-sectional area less than the firstcross-sectional area.